using System.Net;

WebClient client = new WebClient();

client.DownloadFile("https://example.com/file.zip", "local/path/file.zip");

using System.Net.Http;

using System.IO;

async Task DownloadFileAsync(string url, string localPath)

{

    using (HttpClient client = new HttpClient())

    {

        using (HttpResponseMessage response = await client.GetAsync(url, HttpCompletionOption.ResponseHeadersRead))

        {

            using (Stream stream = await response.Content.ReadAsStreamAsync())

            {

                using (FileStream fileStream = new FileStream(localPath, FileMode.Create, FileAccess.Write, FileShare.None, 8192, true))

                {

                    byte[] buffer = new byte[8192];

                    int bytesRead;

                    long totalBytesRead = 0;

                    long totalBytes = response.Content.Headers.ContentLength ?? -1;

                    while ((bytesRead = await stream.ReadAsync(buffer, 0, buffer.Length)) > 0)

                    {

                        await fileStream.WriteAsync(buffer, 0, bytesRead);

                        totalBytesRead += bytesRead;

                        // 處理下載進(jìn)度，例如更新UI

                        Console.WriteLine($"下載進(jìn)度：{totalBytesRead}/{totalBytes}");

                    }

                }

            }

        }

    }

}